Abstract

In order to understand the origin of the Suess wiggles, present in the tree ring 14C record, we have studied the thermoluminescence (TL) of a shallow-water Ionian sea core, in an attempt to provide a record of an indicator
responding to the solar output more promptly than 14C in tree rings. The spectral content of the TL and radiocarbon records is very similar; neverthless, in addition to the 207 y Suess wave (A43.6% ), the TL record shows the second harmonic (103.5 y; A42.4% ), in phase with the envelope of the 11 y solar cycles. This result, obtained by different spectral methods, in particular by Superposition of Epochs (SE) and by Singular Spectrum Analysis (SSA), strongly supports the solar origin of the 200 y Suess wiggles.